Sorry my first post is a fairly morbid one, I need a bit of help from veteran fishkeepers.
I have a very large, outdoor pond with 2 big pumps, it's about 45000L i think. I did have about a dozen fish on it, fairly happily, for 3 years.
The last couple of months, I've had a goldfish develop little lumps on him, so I removed him to a bathtub to try keep him isolated and see if he improved. A couple of weeks later one of my two Ghostfish developed a fuzzy substance on his outsides and so I removed him to a different tub, and tried to treat him with some Blagdons anti fungus but he died.
Today I get home from work and the other ghostfish is belly up. I'm not sure why, the other two had been behaving strangely, hovering near the top of the pond in the winter so I realised something was wrong with them, this one's died completely out of the blue. It has been very cold here (UK) this last week, lots of snow, which did freeze over alot of the surface of the bond but the pumps kept working and kept a section of the surface clear.
I have uploaded a picture of the latest fish, his tail doesn't look too good, can anyone help me with suggestions why I've started having problems and what I could do? Many Thanks